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* Author: TKruse
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#ifndef TRAJECTORYCOSTFUNCTION_H_
#define TRAJECTORYCOSTFUNCTION_H_

#include <base_local_planner/trajectory.h>

namespace base_local_planner
{

/**
* @class TrajectoryCostFunction
* @brief Provides an interface for critics of trajectories
* During each sampling run, a batch of many trajectories will be scored using such a cost function.
* The prepare method is called before each batch run, and then for each
* trajectory of the sampling set, score_trajectory may be called.
*/
class TrajectoryCostFunction
{
public:

    /**
     * 更新常用的变量
     * 毕竟纯虚函数，子类中必须重写该函数
     * General updating of context values if required.
     * Subclasses may overwrite. Return false in case there is any error.
     */
    virtual bool prepare() = 0;

    /** 返回一个局部轨迹的评分，也是纯虚函数
     * return a score for trajectory traj
     */
    virtual double scoreTrajectory(Trajectory &traj) = 0;

    double getScale() { return scale_; }

    void setScale(double scale) { scale_ = scale; }

    virtual ~TrajectoryCostFunction() {}

protected:
    TrajectoryCostFunction(double scale = 1.0) : scale_(scale) {}

private:
    double scale_;
};

}

#endif /* TRAJECTORYCOSTFUNCTION_H_ */
